1. Field of the Invention
This invention relates to a syringe, and to a needleless injector for use with the syringe.
2. DISCUSSION OF THE PRIOR ART
The present inventor has been involved in the field of needleless injectors for many years, his name appearing in many patents, including Canadian Patents Nos. 1,178,503, issued on Nov. 27, 1984; 1,256,343, issued Jun. 27, 1989 and 1,258,019, issued Aug. 1, 1989, and U.S. Pat. Nos. 4,342,310, issued Aug. 3, 1982 and 4,518,385, issued May 21, 1985.
In general, needleless injectors of the type described in the above patents, and the vials or syringes used in the injectors must be carefully manufactured to close tolerances. Moreover, the injectors usually are produced from stainless steel, which prevents the expansion of the plastic syringes containing the medicine. Consequently, the cost of material and production is substantial, and a need exists for a less expensive alternative.